The actress' rep announced in a statement to ET on Monday that "childcare professionals have encouraged a legal agreement accepted and signed by both sides over a week ago."

"In accordance with this agreement, the six children will stay in their mother's custody, and the children will continue therapeutic visits with their father," the statement continued. "This has been determined by childcare professionals to be in the children's best interest."

ET has learned that this agreement is separate from the voluntary safety plan implemented by the Department of Child and Family Services that was extended last month, and is the first step towards a more permanent custody agreement.

"This is what Brad and Angelina have decided between each other for the children," the source added. "The agreement is also indefinite, so there is no time frame to it, it is in place until they decide to make a change... This is a good sign, it is the first step. This means one issue is now off the table for them."

A source close to the Jolie-Pitt child custody dispute tells ET that the agreement referenced in Jolie's rep statement is not permanent. The agreement that is currently in place -- and agreed upon by the couple -- is only temporary until Pitt and Jolie continue to work out a more permanent child custody settlement.

Pitt filed his response to Jolie's divorce petition on Friday and requested joint custody of the couple's six children: 15-year-old Maddox, 12-year-old Pax, 11-year-old Zahara, 10-year-old Shiloh, and 8-year-old twins Knox and Vivienne. Jolie initially requested full custody in her filing in September.

"Back when Angelina first filed for divorce, she said that the reason she filed was for the safety and health and well-being of the kids and that has been her consistent point of view from the beginning," the source explained. "Nothing has changed."

"Unlike Jolie's side, Brad's side is actually attempting to abide by the confidentiality agreement that both parties signed, something Angelina's side has no interest in doing," the source close to the Jolie-Pitt child custody battle tells ET. "From the beginning, Brad only wants to do what's best for the children, and that's not fighting this in the public press."

ET has also learned that the 52-year-old actor will not be withdrawing his petition for shared custody, as it "preserves his rights in the future."

See more about the status of the A-list couple's divorce in the video below.